Muonium

Abstract

A brief review is given of current and future fundamental topics in muonium research including the ground state hfs and Zeeman effect, the Lamb shift in the n=2 state and spontaneous conversion of muonium to antimuonium. The important 1S→2S transition is discussed by K. Jungmann in this volume. It is emphasized that muonium as an atom composed of two leptons is superior to hydrogen for many precise fundamental studies because of the complexities and uncertainties for hydrogen associated with the proton as a hadron.